Spring bar leadframe, method and packaged electronic device with zero draft angle

ABSTRACT

A method includes attaching semiconductor dies to die attach pads of first and second columns of the lead frame; enclosing the semiconductor dies of the respective columns in respective first and second package structures; trimming the lead frame to separate respective first and second lead portions of adjacent ones of the first and second columns of the lead frame; moving the first columns along a column direction relative to the second columns; and separating individual packaged electronic devices of the respective first and second columns from one another.

BACKGROUND

The cost of manufacturing electronic devices can be reduced byincreasing the device count of a given lead frame panel (also referredto as a lead frame sheet or strip). Columns of devices of a lead framesheet can be interdigitated to increase the device density, butinterdigitated devices require trim and form dies to singulate orseparate individual packaged devices from the lead frame. Trim and formdies are also used in electronic device manufacturing to cut and thenform leads of individual devices while part of a lead frame strip havingrows and columns of partially completed devices. However, multiple trimand form die sets are needed for different lead frame stripconfigurations in manufacturing a variety of different devices havingdifferent lead counts and configurations.

SUMMARY

A lead frame is provided according to one aspect. The lead frameincludes a metal structure with prospective device portions arranged inrows and columns along respective first and second directions. Thecolumns include first columns and second columns, where at least some ofthe first columns are adjacent to one of the second columns. The leadframe includes punch structures with a punch bar that extends along thesecond direction from a first end of a respective first column to afirst clamp portion of the metal structure. The lead frame also includesstretch structures with a spring bar that extends from the second end ofa respective first column to a second clamp portion of the metalstructure.

In one example, the spring bar extends along an arcuate path. In oneexample, the respective punch structures include a second punch bar thatextends along the second direction from the first end of the respectivefirst column to the first clamp portion of the metal structure, and therespective stretch structures include a second spring bar that extendsalong a second arcuate path from the second end of the respective firstcolumn to the second clamp portion of the metal structure. In oneexample, the respective spring bar and the second spring bar includefirst and second arcuate portions.

In one implementation, the punch bar is deformable along a thirddirection normal to a plane of the first and second directions, and thespring bar is configured to extend along the second direction to allowmovement of the respective first column along the second directiontoward the first clamp portion of the metal structure.

In one example, the first columns have first device portions thatinclude a respective first die attach pad and respective first leadportions, and the second columns have second device portions thatinclude a respective second die attach pad and respective second leadportions. In one implementation, at least some of the first leadportions of a given one of the first columns are connected to arespective one of the second lead portions of a second device portion ofan adjacent one of the second columns. In one example, the first columnsand the second columns are alternating. In one example, the spring baris configured to extend along the second direction toward the firstclamp portion by a pitch spacing distance of the first lead portions inresponse to deformation of the punch bar by a punch depth dimension.

A method is provided according to another aspect. The method includesattaching first semiconductor dies to respective first die attach padsof first device portions of respective first columns of a lead frame,and attaching second semiconductor dies to respective second die attachpads of second device portions of respective second columns of the leadframe. The method further includes performing a molding process andseparating individual packaged electronic devices of the respectivefirst and second columns from one another. The molding process enclosesthe first semiconductor dies of each respective first columns in asingle respective first package structure, and encloses the secondsemiconductor dies of each respective second column in a singlerespective second package structure.

In one example, the lead frame includes rows that extend along a firstdirection and the first and second columns extend along a perpendicularsecond direction, and the method further includes cutting through thelead frame and the first and second package structures along cut linesbetween the first device portions of the respective first columns andbetween the second device portions of the respective second columns,where the cut lines are parallel to the first direction.

In one example, moving the first columns along the second directionrelative to the second columns includes deforming punch bars proximatefirst ends of the respective first columns along a third directionnormal to a plane of the first and second directions to extend springbars proximate second ends of the respective first columns along thesecond direction. In one implementation moving the first columns alongthe second direction includes moving the first columns by a pitchspacing distance of the first lead portions relative to the secondcolumns.

In one example, before performing the molding process, the methodfurther includes performing an electrical connection process thatelectrically couples at least one of the first lead portions to aconductive feature of the respective first semiconductor die, andelectrically couples at least one of the second lead portions to aconductive feature of the respective second semiconductor die.

In one example, before separating the individual packaged electronicdevices from one another, the method further includes performing a leadtrimming process that cuts through the lead frame along trim lines toseparate respective first and second lead portions of adjacent ones ofthe first and second columns of the lead frame, where the trim lines areparallel to the second direction, and moving the first columns along thesecond direction relative to the second columns.

An electronic device is provided according to another aspect. Theelectronic device includes a molded package structure having a firstside, a second side spaced apart from the first side along a firstdirection, a first end, a second end spaced apart from the first endalong a second direction, as well as a top and a bottom spaced apartfrom the top along a third direction, where the second direction isperpendicular to the first direction and the third direction is normalto a plane of the first and second directions. The electronic devicealso includes a semiconductor die enclosed by the molded packagestructure, first conductive leads along the first side, at least one ofthe first conductive leads being electrically coupled to thesemiconductor die, and second conductive leads along the second side. Atleast one of the second conductive leads is electrically coupled to thesemiconductor die, and the respective first and second ends are planar.

In one example, the respective first and second sides include a firstportion that extends from the top to a mold parting line at a firstangle to a plane of the second and third directions, and a secondportion that extends from the bottom to the mold parting line at asecond angle to the plane of the second and third directions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial top view of a lead frame with interdigitatedcolumns, as well as punch structures and stretch structures atrespective ends of the odd-numbered columns according to an embodiment.

FIG. 2 is a flow diagram of a method according to another embodiment.

FIGS. 3-16 show the lead frame of FIG. 1 in a fabrication process toproduce packaged electronic devices.

FIG. 17 is a perspective view of a packaged electronic device accordingto another embodiment.

FIGS. 18 and 19 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 20 and 21 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 22 and 23 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 24 and 25 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 26 and 27 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 28 and 29 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 30 and 31 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 32 and 33 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

FIGS. 34 and 35 are partial top views of a lead frame withinterdigitated columns and another embodiment of stretch structures atthe bottom ends of the odd-numbered columns.

DETAILED DESCRIPTION

In the drawings, like reference numerals refer to like elementsthroughout, and the various features are not necessarily drawn to scale.Also, the term “couple” or “couples” includes indirect or directelectrical or mechanical connection or combinations thereof. Forexample, if a first device couples to or is coupled with a seconddevice, that connection may be through a direct electrical connection,or through an indirect electrical connection via one or more interveningdevices and connections. One or more operational characteristics ofvarious circuits, systems and/or components are hereinafter described inthe context of functions which in some cases result from configurationand/or interconnection of various structures when circuitry is poweredand operating.

FIG. 1 shows a partial top view of a lead frame 100 formed as a panel orstrip with interdigitated first and second columns 101 and 102,respectively. The lead frame 100 includes a metal structure, such ascopper, with prospective device portions arranged in rows along a firstdirection (e.g., the X direction in FIG. 1), as well as columns along asecond direction (e.g., the Y direction in FIG. 1), where the first andsecond directions are perpendicular to one another. The lead frame is aninterdigitated arrangement, in which respective device portions of thefirst columns 101 are offset or shifted along the second directionrelative to the respective device portions of the second columns 102.

The lead frame 100 has punch structures and stretch structures atrespective ends of the first columns 101 according to one aspect. Thesefeatures facilitate using sawing or other cutting operations to trimdevice leads of the interdigitated columns, followed by molding and sawcutting to separate packaged devices, without requiring lead trim diesfor lead trimming. The punch and stretch structures facilitate movingthe first columns 101 along the column direction after lead trimming andmolding to align the previously offset lead portions of the first andsecond columns 101 and 102. The lead frame 100 is an interdigitatedconfiguration with device portions in each column 101 and 102 thatinclude a respective die attach pad and lead portions with a pitchspacing distance 103. The device portions and respective lead portionsin the first and second columns 101 and 102 are offset or shiftedrelative to one another by a single pitch spacing distance 103. In otherexamples, the offset is an integer number times the pitch spacingdistance 103, where the integer number is 2 or more. In other examples,the interdigitated column offset is not an integer multiple of the pitchspacing distance 103. The lead frame 100 also includes several fixturealignment holes 106 to facilitate X, Y location of the lead frame 100 ina fixture or jig (not shown).

The respective first columns 101 have a first end 111 and a second end112 spaced apart from the respective first end 111 along the seconddirection. The respective first columns 101 also include a punchstructure 114 having a punch bar 115 that extends along the seconddirection from the first end 111 of a respective first column 101 to afirst clamp portion 113 of the metal structure. The punch bar 115 isdeformable along a third direction Z normal to a plane of the respectivefirst and second directions X and Y (e.g., deformable into or out of thepage in FIG. 1). The illustrated punch structures 114 include a secondpunch bar 115 extending along the second direction Y from the first end111 of the respective first column 101 to the first clamp portion 113 ofthe metal structure. Other examples include an integer number of one ormore punch bars 115.

The respective first columns 101 also include a stretch structure 116that has a spring bar 117. The respective first columns 101 have firstdevice portions that individually include a respective first die attachpad 118 and respective first lead portions 119. The spring bar 117extends along an arcuate path from the second end 112 of a respectivefirst column 101 to a second clamp portion 120 of the metal structure.The spring bar 117 is configured to extend along the second direction toallow movement of the respective first column 101 along the seconddirection Y toward the first clamp portion 113 of the metal structure.The spring bar 117 in the example of FIG. 1 is configured to extendalong the second direction toward the first clamp portion 113 by thepitch spacing distance 103 of the first lead portions 119 in response todeformation of the punch bar 115 by a punch depth dimension, asdescribed further below in connection with FIGS. 11-14. The illustratedstretch structures 116 include a second spring bar 117 extending along asecond arcuate path from the second end 112 of the respective firstcolumn 101 to the second clamp portion 120 of the metal structure. Otherexamples include an integer number of one or more spring bars 117. Insome examples, the respective spring bar 117 and the second spring bar117 include first and second arcuate portions. In other examples, thespring bar or bars 117 include an integer number of one or more arcuateportions.

The respective second columns 102 have a first end 121 and a second end122 that is spaced apart from the respective first end 121 along thesecond direction. The respective second columns 102 have second deviceportions that include a respective second die attach pad 128 andrespective second lead portions 129. The lead frame 100 of FIG. 1 hasalternating first columns 101 and second columns 102, in which at leastsome of the first columns 101 are adjacent to one of the second columns102. In other examples, two or more second columns 102 can be adjacentto one another, with the individual first columns 101 adjacent to atleast one of the second columns 102. In the example of FIG. 1, prior tolead trimming, at least some of the first lead portions 119 of a givenone of the first columns 101 are connected to a respective one of thesecond lead portions 129 of a second device portion of an adjacent oneof the second columns 102.

Referring now to FIGS. 2-17, FIG. 2 shows a method 200 for fabricatingpackaged electronic devices, FIGS. 3-16 show the lead frame 100 of FIG.1 undergoing processing according to the method 200, and FIG. 17 shows apackaged electronic device according to another embodiment. The method200 includes providing or creating a lead frame (e.g., lead frame 100)at 202, attaching semiconductor dies to die attach pads of first andsecond columns of the lead frame at 204, electrical connectionprocessing at 206, and enclosing the semiconductor dies of the columns101 and 102 in respective first and second package structures at 208.The method 200 further includes trimming the lead frame 100 at 210 toseparate respective first and second lead portions (e.g., 119 and 129)of adjacent ones of the first and second columns 101 and 102. The method200 also includes lead forming at 212, moving the first columns at 214along a column direction relative to the second columns, and packageseparation at 216 to separate individual packaged electronic devices ofthe respective first and second columns from one another and from thelead frame 100.

At 202 in one example, the starting lead frame 100 is provided orcreated at 202 as a metal structure formed as an interdigitated striphaving rows and respective first and second columns 101 and 102, as wellas respective punch structures and stretch structures 114 and 116 asshown in FIG. 1 above.

The method 200 includes performing a die attach process at 204. FIG. 3shows one example in which a die attach process 300 is performed thatattaches first semiconductor dies 301 to respective first die attachpads 118 of first device portions of respective first columns 101 of thelead frame 100. In this example, the first semiconductor dies 301include conductive features, such as copper bond pads 311 on a top orupper side thereof. In addition, the die attach process 300 attachessecond semiconductor dies 302 to respective second die attach pads 128of second device portions of respective second columns 102 of the leadframe 100. The second semiconductor dies 302 in FIG. 3 includeconductive features 312 on the top side thereof. One or both of thesemiconductor dies 301 or 302 may include conductive features, such assolder bumps, copper pillars, etc. (not shown) that are electricallycoupled to the respective die attach pads 118 and 128, for example,using a flip chip die attach process 300. In another example, the dies301 and/or 302 are epoxied to the respective die attach pads 118 and 128at 204.

The method 200 continues at 206 with wire bonding or other electricalconnection processing. FIG. 4 shows one example, in which an electricalconnection process 400 is performed, including wire bonding thatelectrically couples one or more of the first lead portions 119 to therespective conductive features 311 of the first semiconductor dies 301of the first columns 101. The process 400 also electrically couples oneor more of the second lead portions 129 to the respective conductivefeature 312 of the second semiconductor dies 302 of the second columns102. In one example, the electrical connection process 400 is performedwhile the lead portions 119 and 129 are connected to one another asshown in FIG. 4. The wire bonding process 400 connects first bond wires401 between respective ones of the first lead portions 119 of the firstcolumns 101 and respective conductive features 311 of the firstsemiconductor dies 301. In addition, the wire bonding process 400 inthis example connects second bond wires 402 between respective ones ofthe second lead portions 129 in the second columns 102 and respectiveconductive features 312 of the second semiconductor dies 302.

The method 200 continues at 208 with a molding process that createssingle molded package structures along each of the first and secondcolumns 101 and 102. FIGS. 5 and 6 show one example in which a moldingprocess 500 is performed that encloses the first semiconductor dies 301of each respective first columns 101 in a single respective firstpackage structure 501. In addition, the molding process 500 encloses thesecond semiconductor dies 302 of each respective second column 102 in asingle respective second package structure 502. The process 500 uses amold (not shown) with a single mold cavity with upper and lower portionsthat create tapered sides joined at a mold parting line with an upperfirst draft angle Θ1 and a lower second draft angle Θ2 as shown in FIG.5 to for each individual column 101 and 102. In one example, thecavities associated with the first columns 101 are offset from thecavities associated with the second columns 102 along the seconddirection (Y) by the lead pitch dimension, to create the offset moldedpackage structures 501 and 502 as shown in FIG. 6, although not a strictrequirement of all possible implementations.

The method 200 continues at 210 with column direction lead trimming toseparate the leads of adjacent columns. FIGS. 7 and 8 show one example,in which a lead trimming process 700 is performed that uses a saw to cutthrough the lead frame 100 along trim lines 701 between adjacent pairsof the first and second columns 101 and 102. The process 700 separatesrespective first and second lead portions 119 and 129 of adjacent onesof the first and second columns 101 and 102 which were previously joinedin the starting lead frame 100 of FIG. 1. The process 700 in one exampleuses multiple cutting saw blades that cut along respective trim lines701 concurrently. In another example, a single cutting blade is used tosequentially cut through designated portions of the lead frame 100 alongthe lines 701. Another example uses a laser to cut through thedesignated portions of the lead frame 100 along the trim lines 701. Inthe illustrated example, the trim lines 701 are parallel to one anotherand to the second direction, although not requirements of all possibleimplementations.

The method 200 continues at 212 with lead forming. FIGS. 9 and 10 showone example, in which a lead forming process 900 is performed that formsthe first and second lead portions 119 and 129 of the respective firstand second columns 101 and 102 into gull wing shapes. In other examples,the first and second lead portions 119 and 129 are formed into differentshapes, such as J leads, etc.

The method 200 continues at 214 with translating or moving the firstcolumns 101 along the second direction relative to the second columns102. FIGS. 11-14 illustrate one example, in which the first and secondclamp portions 113 and 120 are clamped by clamping apparatus or otherfeatures of a fixture on which the lead frame 100 is installed (FIGS. 11and 12), and a punch is actuated (FIGS. 13 and 14) along the thirddirection (e.g., the Z direction in FIGS. 11 and 13) to deform the punchbar 115. FIG. 11 shows a section view of a portion of the lead frame 100proximate the first end 111 of one of the first columns 101 taken alongline 11-11 of FIG. 12. A first clamp 1101 engages a top side of theupper edge of the lead frame 100 as shown in FIGS. 11 and 12, and alower clamp 1102 engages the bottom side of the lead frame 100 to holdthe edge of the lead frame 100 stationary as shown in FIG. 11. A lowerdie 1104 (FIG. 11) engages a bottom portion of a section of the punchbar 115, leaving a gap between the lower die 1104 and the lower clamp1102. A punch 1106 is positioned in FIG. 11 above the top side of thepunch bar 115 in a position over the gap between the lower die 1104 andthe lower clamp 1102. As further shown in FIG. 12, a second clamp 1202engages a top side of the bottom edge of the lead frame 100. Similarclamping and punch die features are provided at the ends of each of theindividual first columns 101 as shown in FIG. 12.

FIGS. 13 and 14 show an example, in which a punch process 1300 isperformed that moves the punch 1106 downward (e.g., along the thirddirection “Z” in FIG. 13) normal to the X-Y plane of the respectivefirst and second directions to deform the punch bars 115 proximate firstends 111 of the respective first columns 101. The Z directiondeformation of the punch bars 115 by a punch depth dimension PD (FIG.13) moves the first columns 101 along the second direction relative tothe second columns 102 by the pitch spacing distance 103 of the firstlead portions 119 (e.g., upward along the direction of the arrows inFIG. 14).

The movement of the first columns 101 along the second direction extendsthe spring bars 117 of the first columns 101 along the second directionas shown in FIG. 14. In one example, the punch 1106 is translated alongthe Z direction by an automated servo system (not shown). In anotherexample, the punch 1106 is manually actuated. In one example, the punchdepth dimension PD and the resulting Z direction movement of the punch1106 are tailored according to the pitch spacing distance 103 or anyother desired amount of Y direction movement of the first columns 101relative to the second columns 102, as well as according to thethickness and material of the lead frame 100.

The method 200 continues at 216 with row direction cutting to separatethe individual packaged electronic devices. The cutting at 216 alsocreates molded package and with a zero draft angle. FIGS. 15 and 16 showone example, in which a sawing process 1500 is performed along cut lines1501 to separate individual device portions of the column-length moldedstructures, and to create first and second ends 1502 and 1503,respectively, for individual packaged electronic devices 1511 and 1512of the respective first and second columns 101 and 102. The sawingprocess 1500 separates individual packaged electronic devices 1511, 1512of the respective first and second columns 101 and 102 from one another.In another example, the packaged electronic devices 1511 and 1512 areseparated from one another and from the lead frame 100 using a differentcutting technique, such as laser cutting. Because the columns 101 and102 were previously aligned by the punch operation at 214, the cut lines1501 extend between the first device portions of the respective firstcolumns 101 and between the second device portions of the respectivesecond columns 102. In this example, the cut lines 1501 are parallel tothe first direction, although not a requirement of all possibleimplementations.

The method 200 and the inclusion of the punch structures 114 and stretchstructures 116 facilitate improved lead frame strip device densitythrough interdigitated starting lead frame configurations (e.g., leadframe 100), while allowing cutting operations for lead trimming as wellas device separation, and without requiring multiple trim and form diesets to accommodate multiple lead count and package sizes duringintegrated circuit manufacturing. The package saw cutting at 216 can beeasily adapted to different lead frame configurations by changing a sawequipment recipe or programming, without requiring multiple tooling sets(e.g., punch die sets) to accommodate multiple lead counts. In oneexample, a jig (not shown) is used for manual pressing of the punch 1106such that the Y direction translation of the first columns 101 providesaccurate and repeatable pitch correction according to the punch depthPD, where the jig includes a handle, a hinge punch stopper, a track, anda jig base (not shown). The spring bar 117 in the example of FIG. 1 isconfigured to extend along the second direction toward the first clampportion 113 by the pitch spacing distance 103 of the first lead portions119 in response to deformation of the punch bar 115 by the punch depthdimension PD as shown in FIGS. 13 and 14.

FIG. 17 shows a perspective view of an example packaged electronicdevice 1511 (e.g., an integrated circuit or IC) produced by the method200 of FIG. 2 using the starting lead frame 100 of FIG. 1. Theelectronic device 1511 includes the molded package structure 501 with afirst side 1701, an opposite second side 1702 spaced apart from thefirst side 1701 along the first direction (X), as well as the first end1502 and the second end 1503 spaced apart from the first end 1502 alongthe second direction (Y). The electronic device 1511 also includes a top1706 and a bottom 1708 spaced apart from the top 1706 along the thirddirection (Z). The electronic device 1511 in this example includes thesemiconductor die 301 (e.g., FIG. 4 above) enclosed by the moldedpackage structure 501, as well as first conductive leads 119 along thefirst side 1701 and second conductive leads 119 along the second side1702 of the package structure 501. The leads 119 have the pitch spacing103 as previously discussed. In one example, one or more of the firstconductive leads 119 is/are electrically coupled to the semiconductordie 301 and one or more of the second conductive leads 119 is/areelectrically coupled to the semiconductor die 301 (e.g., via bond wires401 shown in FIG. 4).

The sawing process used to separate the packaged electronic devices 1511and 1512 creates planar first and second ends 1502 are 1503 as shown inFIG. 17. In one example, the individual first and second sides 1701 and1702 each include a first portion 1711 that extends from the top 1706 toa mold parting line 1704 at a non-zero first angle Θ1 to the Y-Z planeof the second and third directions. In addition, the individual firstand second sides 1701 and 1702 include a second portion 1712 thatextends from the bottom 1708 to the mold parting line 1704 at a secondnon-zero angle Θ2 to the Y-Z plane. In one example, the first and secondangles are equal (e.g., Θ1=Θ2), although not a strict requirement of allpossible implementations.

The stretch structures 116 and associated spring bars 117 at the secondends 112 of the first columns 101 in FIG. 1 provide a single yield pointdesign that is good for manufacturability. FIGS. 1 and 10 show thespring bars 117 before punch actuation, and FIG. 14 shows the stretchedspring bars 117 moved 0.409 inches in response to punch actuation to apunch depth PD (FIG. 13) of 0.032 inches. In certain examples, thespring bar 117 has a single arcuate portion. In other examples, thespring bar 117 has multiple arcuate portions. Different implementationshave one or more yield locations for the individual spring bars 117.

FIGS. 18-35 show different example implementations of the spring barsand stretch structures proximately the second ends 112 of the firstcolumns 101. These examples include the lead portions 119 and 129, thealignment holes 106, the molded package structures 501 and 502, andlower clamps 1202 as previously described.

FIGS. 18 and 19 show partial top views of a lead frame 1800 withinterdigitated columns as previously described. FIGS. 18 and 19 showanother embodiment of stretch structures 1816 and associated spring bars1817 at the second ends 112 of the odd-numbered columns. FIG. 18 showsthe lead frame 1800 in interdigitated form prior to stretching, and FIG.19 shows the lead frame 1800 after the first columns have been movedupward along the second (e.g., Y) direction. In this example, the punchdepth PD of 0.025 inches and a second direction movement of 0.397inches.

FIGS. 20 and 21 show partial top views of a lead frame 2000 withinterdigitated columns as previously described. FIGS. 20 and 21 showanother embodiment of stretch structures 2016 and associated spring bars2017 at the second ends 112 of the odd-numbered columns. FIG. 20 showsthe lead frame 2000 in interdigitated form prior to stretching, and FIG.21 shows the lead frame 2000 after the first columns have been movedupward along the second (e.g., Y) direction. In this example, the punchdepth PD of 0.022 inches and a second direction movement of 0.431inches.

FIGS. 22 and 23 show partial top views of a lead frame 2200 withinterdigitated columns as previously described. FIGS. 22 and 23 showanother embodiment of stretch structures 2216 and associated spring bars2217 at the second ends 112 of the odd-numbered columns. FIG. 22 showsthe lead frame 2200 prior to stretching, and FIG. 23 shows the leadframe 2200 after the first columns have been moved upward along thesecond direction, with a punch depth PD of 0.020 inches and a seconddirection movement of 0.412 inches.

FIGS. 24 and 25 show partial top views of a lead frame 2400 withinterdigitated columns as previously described. FIGS. 24 and 25 showanother embodiment of stretch structures 2416 and associated spring bars2417 at the second ends 112 of the odd-numbered columns. FIG. 24 showsthe lead frame 2400 prior to stretching, and FIG. 25 shows the leadframe 2400 after the first columns have been moved upward with a punchdepth PD of 0.020 inches and a second direction movement of 0.047inches.

FIGS. 26 and 27 show partial top views of a lead frame 2600 withinterdigitated columns as previously described. FIGS. 26 and 27 showanother embodiment of stretch structures 2616 and associated spring bars2617 at the second ends 112 of the odd-numbered columns. FIG. 26 showsthe lead frame 2600 prior to stretching, and FIG. 27 shows the leadframe 2600 after the first columns have been moved upward with a punchdepth PD of 0.118 inches and a second direction movement of 0.046inches.

FIGS. 28 and 29 show partial top views of a lead frame 2800 withinterdigitated columns as previously described. FIGS. 28 and 29 showanother embodiment of stretch structures 2816 and associated spring bars2817 at the second ends 112 of the odd-numbered columns. FIG. 28 showsthe lead frame 2800 prior to stretching, and FIG. 29 shows the leadframe 2800 after the first columns have been moved upward with a punchdepth PD of 0.023 inches and a second direction movement of 0.400inches.

FIGS. 30 and 31 show partial top views of a lead frame 3000 withinterdigitated columns as previously described. FIGS. 30 and 31 showanother embodiment of stretch structures 3016 and associated spring bars3017 at the second ends 112 of the odd-numbered columns. FIG. 30 showsthe lead frame 3000 prior to stretching, and FIG. 31 shows the leadframe 3000 after the first columns have been moved upward with a punchdepth PD of 0.023 inches and a second direction movement of 0.454inches.

FIGS. 32 and 33 show partial top views of a lead frame 3200 withinterdigitated columns as previously described. FIGS. 32 and 33 showanother embodiment of stretch structures 3216 and associated spring bars3217 at the second ends 112 of the odd-numbered columns. FIG. 32 showsthe lead frame 3200 prior to stretching, and FIG. 33 shows the leadframe 3200 after the first columns have been moved upward with a punchdepth PD of 0.042 inches and a second direction movement of 0.011inches.

FIGS. 34 and 35 show partial top views of a lead frame 3400 withinterdigitated columns as previously described. FIGS. 34 and 35 showanother embodiment of stretch structures 3416 and associated spring bars3417 at the second ends 112 of the odd-numbered columns. FIG. 34 showsthe lead frame 3400 prior to stretching, and FIG. 35 shows the leadframe 3500 after the first columns have been moved upward with a punchdepth PD of 0.036 inches and a second direction movement of 0.421inches.

The designs of FIGS. 1, 22-23, 32-33 and 28-29 give comparable pitchcorrection result with the spring bars 1817 of FIGS. 18 and 19. Thedesigns of FIGS. 20-21, 24-25, 26-27, 30-31 and 34-35 give higher valueof pitch correction along the second direction.

The above examples are merely illustrative of several possibleimplementations of various aspects of the present disclosure, whereinequivalent alterations and/or modifications will occur to others skilledin the art upon reading and understanding this specification and theannexed drawings. Modifications are possible in the described examples,and other implementations are possible, within the scope of the claims.

1-20. (canceled)
 21. A method, comprising: attaching first semiconductordies to respective first die attach pads of first device portions ofrespective first columns of a lead frame; attaching second semiconductordies to respective second die attach pads of second device portions ofrespective second columns of the lead frame, the lead frame includingrows that extend along a first direction and the first and secondcolumns extend along a second direction, the first direction beingperpendicular to the second direction; covering the first semiconductordies of each respective first column in a single respective firstpackage structure; covering the second semiconductor dies of eachrespective second column in a single respective second packagestructure; cutting the lead frame along trim lines to separaterespective first and second lead portions of adjacent ones of the firstand second columns of the lead frame, the trim lines being parallel tothe second direction; moving the first columns along the seconddirection relative to the second columns; and performing a cuttingprocess that cuts through the lead frame and the first and secondpackage structures along cut lines between the first device portions ofthe respective first columns and between the second device portions ofthe respective second columns, the cut lines being parallel to the firstdirection.
 22. The method of claim 21, wherein moving the first columnsalong the second direction relative to the second columns comprises:deforming punch bars proximate first ends of the respective firstcolumns along a third direction normal to a plane of the first andsecond directions to extend spring bars proximate second ends of therespective first columns along the second direction.
 23. The method ofclaim 21, wherein moving the first columns along the second directionrelative to the second columns comprises moving the first columns by apitch spacing distance of the first lead portions relative to the secondcolumns.
 24. The method of claim 21, further comprising, beforeperforming the molding process: performing an electrical connectionprocess that: electrically couples at least one of the first leadportions to a conductive feature of the respective first semiconductordie of the respective first device portions of the respective firstcolumns; and electrically couples at least one of the second leadportions to a conductive feature of the respective second semiconductordie of the respective second device portions of the respective secondcolumns.
 25. A method, comprising: attaching first semiconductor dies torespective first die attach pads of first device portions of respectivefirst columns of a lead frame; attaching second semiconductor dies torespective second die attach pads of second device portions ofrespective second columns of the lead frame; covering the firstsemiconductor dies of each respective first columns in a singlerespective first package structure; covering the second semiconductordies of each respective second column in a single respective secondpackage structure; moving the first columns relative to the secondcolumns; and separating individual packaged electronic devices of therespective first and second columns from one another.
 26. The method ofclaim 25, wherein moving the first columns relative to the secondcolumns comprises: deforming punch bars proximate first ends of therespective first columns to extend spring bars proximate second ends ofthe respective first columns along the second direction.
 27. The methodof claim 25, wherein moving the first columns comprises moving the firstcolumns by a pitch spacing distance of the first lead portions relativeto the second columns.
 28. The method of claim 25, further comprising,before covering the first semiconductor dies and second semiconductordies: performing an electrical connection process that: electricallycouples at least one of the first lead portions to a conductive featureof the respective first semiconductor die of the respective first deviceportions of the respective first columns; and electrically couples atleast one of the second lead portions to a conductive feature of therespective second semiconductor die of the respective second deviceportions of the respective second columns.
 29. The method of claim 25,further comprising cutting the lead frame along trim lines to separaterespective first and second lead portions of adjacent ones of the firstand second columns of the lead frame, the trim lines being parallel tothe second direction;
 30. The method of claim 25, further comprisingcutting through the lead frame and the first and second packagestructures along cut lines between the first device portions of therespective first columns and between the second device portions of therespective second columns, the cut lines being parallel to the firstdirection.
 31. The method of claim 30, further comprising, cuttingthrough the lead frame and the first and second package structures alongcut lines between the first device portions of the respective firstcolumns and between the second device portions of the respective secondcolumns, the cut lines being parallel to the first direction.
 32. Amethod, comprising: attaching semiconductor devices to respective dieattach pads of a lead frame; covering the semiconductor devices inpackage structures; moving at least some of the package structures withrespect to others of the package structures; and separating the movedand unmoved package structures into individual packaged semiconductordevices.
 33. The method of claim 32, wherein multiple semiconductordevices are in any one package structure.
 34. The method of claim 32,wherein more than one package structures are on the lead frame.
 35. Themethod of claim 32, wherein first ones of the semiconductor devices areattached to respective first die attach pads of first device portions ofrespective first columns of the lead frame and second ones of thesemiconductor devices are attached to respective second die attach padsof second device portions of respective second columns of the leadframe.
 36. The method of claim 32, wherein one portion of the separatingincludes cutting the lead frame along trim lines to separate respectivefirst and second lead portions of adjacent ones of the first and secondcolumns of the lead frame, the trim lines being parallel to the seconddirection.
 37. The method of claim 36, further comprising moving thefirst columns along the second direction relative to the second columns.38. The method of claim 36, wherein moving the first columns along thesecond direction relative to the second columns comprises moving thefirst columns by a pitch spacing distance of the first lead portionsrelative to the second columns.
 39. The method of claim 32, wherein oneportion of the separating includes performing a cutting process thatcuts through the lead frame and the first and second package structuresalong cut lines between the first device portions of the respectivefirst columns and between the second device portions of the respectivesecond columns, the cut lines being parallel to the first direction ofthe lead frame including rows that extend along a first direction andthe first and second columns extend along a second direction, the firstdirection being perpendicular to the second direction.
 40. The method ofclaim 32, further comprising, before performing the molding process:performing an electrical connection process that: electrically couplesat least one of the first lead portions to a conductive feature of therespective first semiconductor die of the respective first deviceportions of the respective first columns; and electrically couples atleast one of the second lead portions to a conductive feature of therespective second semiconductor die of the respective second deviceportions of the respective second columns.